South Carolina Sen. Jim DeMint, who has built a reputation in the Senate as a leader for the Tea Party movement announced on Thursday that he is resigning his seat and has accepted the presidency of the Heritage Foundation, a conservative think tank. His resignation will be effective in January.

"It's been an honor to serve the people of South Carolina in the United States Senate for the past eight years, but now it's time for me to pass the torch to someone else and take on a new role in the fight for America's future," DeMint said in a statement.

The resignation has taken the nation's capital by surprise.

"No one saw this coming," said Concerned Women of America's Penny Nance. "This certainly opens up leadership opportunities for the likes of Sens. Marco Rubio, Mike Lee and others who are young, intelligent and conservative."

DeMint, who is two years into his second six-year term, is a staunch conservative and has often run afoul of party leadership when he has demanded they hold the line on taxes and social issues.

A proponent of term limits, the South Carolina conservative has already made it clear that he would not seek a third term in 2016.

"I'm leaving the Senate now, but I'm not leaving the fight. I've decided to join The Heritage Foundation at a time when the conservative movement needs strong leadership in the battle of ideas. My constituents know that being a senator was never going to be my career."

Senate Majority Leader Mitch McConnell received word of DeMint's departure Thursday morning. Interestingly, McConnell's wife, former Bush cabinet member Elaine Chao, is a distinguished fellow at The Heritage Foundation and will be reporting to DeMint.

"We're sorry to see Jim go," said McConnell. He's had a distinguished career."

Tea Party Patriot National Coordinator Jenny Beth Martin praised DeMint for his work on behalf of conservatives and vowed to work with him in his new role.

"Tea Party Patriots have been honored to work alongside Sen. DeMint for fiscal responsibility, free markets and Constitutionally limited government," said Martin in a written statement. "While we are sad to lose a strong, conservative voice in the Senate, he will continue to be a courageous advocate for our principles in his new role. As Washington flounders in the midst of the so-called 'fiscal cliff' crisis, it's clear we need more leaders like Sen. DeMint to stand firm for Americans in the face of stiff opposition."

DeMint made his announcement at the Heritage headquarters, just blocks from the Capitol this morning in front of dozens of staffers.

South Carolina Gov. Nikki Haley, a Republican, is tasked with appointing an interim senator until 2014, when a special election would be held to serve out the remaining two years on his current term.

Clemson University professor David Woodard, who co-wrote a book with DeMint in 2007, told USA Today that DeMint probably has grown frustrated with his role in the minority and the lack of Republican efforts to gain a majority in the recent elections.

"I am absolutely not surprised one bit that his happened," said Woodard. DeMint. "He could stay there as long as he wanted to stay. But he really wants to do policy and he thinks the Heritage Foundation is the place to do that."

South Carolina, a deep red state, will most likely send another Republican to replace DeMint in 2014. Names being tossed about already are GOP Reps. Trey Gowdy, Tim Scott and Mick Mulvaney. Others include state Sen. Tom Davis and state Treasurer Curtis Loftis.

DeMint will oversee an $80 million dollar budget and a staff of over 250 at the 39-year-old think tank. He will succeed the organization's current president, Ed Feulner.